In an optical system, especially a high-performance optical system, it is often necessary for lenses or other optical components to be very precisely aligned with respect to each other. A positional tolerance between the optical axes of two parts may need to be as small as a few microns.
As an example, one known configuration involves two lenses, where one lens has a recess that receives the other lens. The recess has a radially-inwardly facing cylindrical surface, and the lens in the recess has a radially-outwardly facing cylindrical surface, the two cylindrical surfaces differing only slightly in diameter, and being closely adjacent each other. Assembling or disassembling the two lenses can be very difficult because, if one lens is tilted even slightly with respect to the other during assembly or disassembly, the cylindrical surfaces bind and resist relative movement of the lenses.
To avoid this problem, it is possible to adjust the diameter of at least one of the cylindrical surfaces, in order to increase the space between the lenses. In order to align these two lenses, it is possible to use optical tooling, along with some additional structure that holds the lenses in place after they have been aligned. However, this approach is time consuming, and provides a reduced level of accuracy.
While these pre-existing approaches have been generally adequate for their intended purposes, they have not been satisfactory in all respects. No single existing approach provides fast and reliable assembly or disassembly of two optical components, with a high degree of centering accuracy, and without time-consuming alignment.